In the age of information, the field of communications devices has experienced among the most rapid rates of innovation of any area of technology. As the requirements of communication devices continue to increase, methods for faster, cheaper, and more reliable data transfer are continuously developed. Orthogonal frequency-division multiplexing (OFDM) has developed as a method for reliable, high-volume data transfer in both wire and wireless mediums that can require simpler device architecture than other methods. Wideband digital applications such as digital television, audio broadcasting, wireless networking, and broadband internet have become popular applications for OFDM transmission.
Generally, in OFDM transmission, when the transmission channel is fixed in time and there is no Doppler effect, cross-talk between subchannels can be eliminated by selecting subcarrier frequencies so that subcarriers are orthogonal to each other. Hence, data sent through such OFDM transmission can be recovered from a received signal by estimating the channel in each subcarrier and compensating the signal for the estimated channel without taking into account inter-carrier interference (ICI).
However, in certain cases, such as when the Doppler Effect is present, subcarrier frequencies can become distorted. As a result, the subcarriers may no longer be orthogonal, resulting in cross-talk between subchannels and inter-carrier interference. In these situations, methods for data recovery that do not take into account inter-carrier interference can be insufficient to retrieve the transmitted data. What is needed is a system and method that estimates the channel taking into account inter-carrier interference so that channel equalization can compensate for inter-carrier interference based on the estimated channel.